Hydrocarbon gels containing metal alkoxy gellants and a dehydrating agent

ABSTRACT

A composition of matter comprising a gelatinous hydrocarbon containing a minor amount of a compound having either the formula MOR or

United States Patent [19] Whitney Nov. 27, 1973 [54] HYDROCARBON GELS CONTAINING METAL ALKOXY GELLANTS AND A DEHYDRATING AGENT [75] inventor: Thomas A. Whitney, Linden, NJ.

[73] Assignee: Esso Research and Engineering Company, Linden, NJ.

[22] Filed: Mar. 3, 1972 [2]] Appl. No.: 231,746

[52] US. Cl. 44/7 C, 44/7 D [51] Int. Cl C10l 7/00 [58] Field of Search 44/7 D, 7 B, 7 A,

[56] References Cited UNITED STATES PATENTS 3,488,370 l/l970 Leary et al 44/7 A 3,6l5,285 10/1971 Whitney et al 44/7 C Primary Examiner-Benjamin R. Padgett Attorney-Leon Chasan et al.

[57] ABSTRACT A composition of matter comprising a gelatinous hydrocarbon containing a minor amount of a compound having either the formula MOR or X(Q )D (R!!!)y I in combination with a compound having the formula M'(OR') wherein M is'one selected from the group consisting of Group IA metals; M is one selected from the group consisting of Group lllA metals; R and R are independently selected from the group consisting of C C straight or branched hydrocarbyl radicals; R and'R are the same or different wherein each is a C C straight or branched hydrocarbyl radical; Q is O or N; A is a hydrocarbyl group containing from 2 to 4 methylenic carbon atoms having 0 to 2 substituents, said substituents being one selected from the group consisting of C C, alkyl, C -C cycloalkyl, phenyl, C -C alkenyl, C -C alkynyl, Cl, Br, I; n is an integer ranging from 1 to 10 inclusive; x is an integer and is either 1 or 2 depending on the valence of O; y is either 0 or 1 depending on the valence of Q; in combination with either an effective amount of a dehydrating agent sufficient to prevent hydrolytic degelation or iron powder to provide the composition with magnetic properties.

15 Claims, No Drawings HYDROCARBON GELS CONTAINING METAL ALKOXY GELLANTS AND A DEI-IYDRATING AGENT BACKGROUND OF THE INVENTION The gelatinization of hydrocarbons has been attempted repeatedly in the past. An almost endless variety of compounds have been utilized in order to effect the gelatinization; they include soap powder, beeswax, various alcohols, waxes, organic acids and bases, cellulose nitrate, soaps, high polymers, etc. These compounds have met with varying degrees of success but were deficient because generally a relatively large quantity of gelling agent was required to give satisfactory results and the hydrocarbon gels were quite temperature sensitive. In addition, the original fluidity of the hydrocarbon could not be restored.

There is a definite need for a technique to gelatinize hydrocarbons; the primary use for such gelatinized hydrocarbons would be in the fuels area. Specifically, helicopter fuels would have to be confined as much as possible if the fuel tank enclosing them were to be perforated. In the event that gasoline or jet fuel were to spray, the destruction caused by a fire would be increased several-fold.

There are, however, many areas outside of fuel consumption where it would be desirous to gelatinize a hydrocarbon such as in preparing a fiuid for hydraulic gas or oil well fracturing or in greases, where it is required that the gels have a reduced water sensitivity. The prep 3 aration of the hydrocarbon gels are described in detail in U.S. Pat. No. 3,615,285. The subject inventive concept relates to an improvement in the composition by reducing its water sensitivity.

SUMMARY OF THE INVENTION A composition of matter comprisinga gelatinous hydrocarbon containing a minor amount of a compound having either the formula MOR or in combination with a compound having the formula M'(OR) wherein M is one selected from the group consisting of Group IA metals; M is one selected from the group consisting of Group IIIA metals; R and R' are independently selected from the group consisting of C -C straight or branched hydrocarbyl radicals; R" and R' are the same or different wherein each is a C -C straight or branched hydrocarbyl radical; Q is or N; A is a hydrocarbyl group containing from 2 to 4 methylenic carbon atoms having 0 to 2 substituents, said substituents being one selected from the group consisting of C -C alkyl, C -C cycloalkyl, phenyl, C -C alkenyl, C -C alkynyl, Cl, Br, I; n is an integer ranging from 1 to 10 inclusive; x is an integer and is either l or 2 depending on the valence of O; y is either 0 or 1 depending on the valence of Q; in combination with either an effective amount of a dehydrating agent sufficient to prevent hydrolytic degelation or iron powder to provide the composition with magnetic properties. These hydrocarbons may be liquid under ambient conditions or may be liquefied by means of pressure addition. The hydrocarbons may be aromatic or aliphatic which would include both saturated and unsaturated compounds as well as cyclic hydrocarbons. It is preinvention. Regarding the aliphatic compounds, they include C, through C alkanes and alkenes, normal and branched chain as well as cyclic. Specific compounds which fall within these categories and would be preferred are the C to C alkanes and alkenes as exemplified by the following: propane, butane, pentane, hexane, cyclohexane, cyclohexene, methylcyclopentane, decane, decalin, cetane, l-heptene, 4-nonene, isooctane, n-octylcyclohexane, l,4-di-n-butylcyclohexane, norbomene.

Substituted alkanes in which one or more hydrogens have been replaced by halogen such as Cl, Br, N0 CN, etc. may also be utilized.

Gelatinization of mixtures of various types of hydrocarbons are also intended to be within the. scope of this invention. Thus, the hydrocarbon may encompass a kerosene fraction which boils between and 350 C. or naphtha boiling between 30 and 150 C. or diesel fuel typically characterized as having a cetane number of 50, a boiling range of 180 to 350 C. and a gravity of 37. The hydrocarbon mixture may also be liquefied petroleum gas (LPG) which is generally about 95 per- 0 cent C hydrocarbons with the remaining 5 percent split half and half between C and C hydrocarbons.

In particular, jet fuels which may overlap both of the above ranges are intended to be included within the instant invention.

The two compositions needed to effect the gelling are either MOR or in combination withMfjQRh. S uch combination is 7 necessary for the gelling to be effected within the hydrocarbon; that is to say, if either one of the two compounds are not present with the M'(OR') the hydrocarbon will not gel. The degree of gelling within the hydrocarbon will be dependent upon the particular elements utilized within the formulae, this will be discussed in more detail below.

Turning to the gelling compositions M may be any group IA metal, i.e., lithium, sodium, or potassium. Lithium is preferred if it is desirous to have a more viscous hydrocarbon based on the total weight per cent of gelling reagents added to the hydrocarbon. M may be any Group IIIA metal, preferably boron or aluminum.

R and R are independently selected from the group consisting of C, to C hydrocarbyl radicals. Specifically, C through C hydrocarbyl radicals are preferred. This would include C through C aryl radicals, including anthracene and naphthalene. Other aryl radicals which may be utilized include the following: C HsCHg, C5H5(CHg) where n 2 to I4.

Alkyl and alkenyl radicals may also be utilized for R and R, it is preferred that the alkyl and alkenyl radicals are C, to C radicals. Most preferred radicals for R are C; to C alkyl radicals either normal or branched; most preferred radicals for R are the C to C alkyls normal and branched. Cyclo alkyl radicals and cycle alkenyl radicals may also be utilized for R and R. The cyclic radicals would fall within the range of C to C preferably C to C and most preferably C to C Typical cyclic alkyl and alkenyl radicals which may be utilized are the following: cyclopentyl, cyclohexyl.

In the hydrocarbon gelling reagent having the general formula ROM M(OR' R may also be derived from monoethers of polyalkyleneoxides such as polyethylene oxide, polypropylene oxide, polystyrene oxide, etc., as well as from amino alcohols. The alkoxides of the monoethers of polyalkylene oxides may be characterized by the formula where Q is O or N, R" and R' are the same or different C to C hydrocarbon radical straight or branched, A is a hydrocarbon group containing 2 to 4 methylenic carbon atoms having 0 to 2 substituents each containing 1 to 6 carbon atoms, M is a Group IA metal, preferably lithium or sodium, n is an integer ranging from one to 10 inclusive, x is an integer and is either 1 or 2 de pending on the valence of Q and y is either 0 or 1 depending on the valence of Q.

Alkoxides derived from monoethers of polyalkylene oxides can be liquid compounds having high hydrocarbon solubility. This property is particularly desirable for the convenience it lends to the preparation of thickened or gelled hydrocarbons. Such convenience is most desirable in field operations such as gas and oil well fracturing.

The molar ratio of the two gelling compounds may be varied from 3:1 to 1:3 equivalents of either MOR or to M(OR);,. Preferably a 1:1 molar ratio is employed.

The weight per cent of gelling reagents employed may be varied from A to 5 percent. The preferred range is A to 3 percent and the most preferred range is 74 to 2 percent based on the total weight of hydrocarbon to be gelled.

Thus, from the above preferred compounds having the designation MOR are as follows: n-CJI OLi, tert- C4Hg0Li, n-CaH11oLi, Z-C H OLi, n-C H OLi, C H OLi, Z-ethylhexyl-OLi, iso-hexadecyl OLi, tert- CqH ONa, 2-CgH17ONa.

The preferred compounds having the formula M(OR');, are as follows: B(OCH(CI-I B(OC H o u)a 1a aa)a, K -Q QM ti ll)3v l( a)z)a. ie aa)a- Preferred compounds having the designation CIHQNCHICHjO CHQCHzO Li, CgHsO CHQOHZNCHiCHQO Li,

CuHsNCHgCHgO CHzCHzNCHzCHgO Li H: rHn

The hydrocarbon gel may be prepared by combining separate solutions of the two compounds. The compound MOR may be suspended or dissolved in one part of the hydrocarbon to be gelled and the compound M(OR' is dissolved in a separate portion of the same or a different hydrocarbon and the two are combined with stirring at below or above ambient temperature. Pressure may vary from subatmospheric to superatmospheric but ambient pressure is preferred. Alternatively, the compound designated as MOR may be formed in situ by conversion of a hydrocarbon solution of a proper alcohol into its alkoxide by addition of an appropriate reagent such as n-butyl lithium and then add ing to the hydrocarbon alkoxide solution or suspension the other compound either neat or as a solution in the same or a different hydrocarbon.

During the addition of the compounds to the hydrocar-bon, temperatures should be between and +200 C., preferably 0 to C. and mostpreferably 20 to 30 C.

The gel takes from a few seconds to 30 minutes to form. Typically, the two compounds are added all at once with stirring.

In order to restore the original fluidity of the hydrocarbon the following technique is utilized:

To the gel is added a sufficient quantity (i.e, 5 to 1,000 moles in excess of the quantity of MOR and M(OR) present in the gel) of a polar material such as water or metha-nol and the entire mixture is thoroughly mixed.

If it is desired to restore only part of the original fluidity of the hydrocarbon, a gel may be diluted with the same or a different hydrocarbon, with thorough mixing until the desired viscosity is obtained, or by addition of less than 5 moles polar material.

To make the improved hydrocarbon gel of the subject invention, a dehydrating agent in an amount suffrcient to resist hydrolytic degelation is incorporated with the two gelling compounds described hereinabove. The dehydrating agent can be one selected from the group consisting of powdered CaCh, MgSO Ca,C, Na SO CaO, NaOI-I, KOl-I, P 0 boric anhydrides, CaCO ZnCl, and BaO. It is to be understood that whatever is added to the gel would have to be compatible with the gel forming reagents and the gel network or else the gel would be destroyed. Those materials which have been found to not be compatible with the gelling reagents are protonic acids such as H 80, and H PO as well as reactive metals such as sodium and very strong oxidizing agents such as Mg(ClO The added reagents or dehydrating agents will preferentially react with water or other polar materials thus affording the hydrocarbon gel an increased resistance to hydrolysis and/or reduction in viscosity. In addition, the dehydrating agent could also serve as a pore plugging agent in applications of the hydrocarbon gels for gas and oil well fractur-ing. Such a use wherein the components are MOR and M'(OR) is described in a copending patent application bearing Ser. No. 231,525 filed on Mar. 3, 1972.

The same considerations apply to the use of the gels in secondary oil recovery applications.

The amount of the dehydrating agent employed in the gel ranges from 0.1 wt. percent to 90 wt. percent, preferably from 0.5 wt. percent to wt. percent which depends upon how great an increased resistance to hydrolytic degelation is desired.

A gas or oil well fracturing fluid using the improved gels of this invention may be composed of from 1 to about 90 percent by weight of sand or other coarse solid material.

Another type of improved gel of this invention is a magnetic hydrocarbon gel which is prepared by incorporating iron powder in a gel produced by the method described hereinabove. Such magnetic gels could have uses in electrical and electronic devices or in magnetic field displays. Other uses could include lifting or transporting hydrocarbons by means of magnetic and electric fields.

The amount of magnetic material such as iron filings contained in the gel may range from 0.1 to 95 percent by weight, preferably from 1 percent to 20 percent by weight.

The following examples are employed to demonstrate the applicability of the subject invention.

EXAMPLE 1 To 24 grams of n-heptane was added 0.25 g of C l-l OLi (1.0 mmole), the mixture was heated with stirring to 60 C. and 2.35 g of anhydrous Na,SO was added. To the alkoxide solution containing Na SO was added a solution of 0.23 g (l mmole) of B(OC H in enough heptane to make 24 g of solution. A gel was nearly instantly produced and the stirring bar was removed after 10 seconds leaving a soft gel with Na SO evenly distributed. After 24 hours no settling of the Na SO was evident. The Na SO content of gel was 5 weight per cent.

The gel was aged for 46 days with frequent shaking in order to determine if the added Na SO would have any deleterious effect on the gel properties. No such effect was detected.

Water, 0.5 ml, was then injected into the gel through a septum in the cap of the container and the whole was shaken vigorously for minutes. The gel did not break down in that time. It did break down after about 1 hour of alternate periods of shaking and standing.

However, as compared to the control which was an identical heptane gel, the above gel was much more water resistant. The control gel upon addition of 0.5 ml of water followed by shaking broke down in several seconds.

EXAMPLE 2 A gel was prepared similar to that described in Example 1 except that 4.7 g of CaO was added to the alkoxide solution. (A separate gel was also prepared, but the CaO (4.7g) was added to the borate solution to demonstrate that gel forma-tion would occur regardless of which reagent of the gelling reagents the dehydrating agent was added to.) The gel contained 10 per cent by weight of CaO.

The gel was aged 46 days and no change in its properties was noted. Water, 0.5 ml. was then added and the mixture was vigorously shaken for 45 minutes. It did not break down in that time. After about 1 hour the gel did break down nevertheless it was much more stable toward water than an identical gel without added CaO.

EXAMPLE 3 A gel was prepared similar to that described in Example 1 except that 4.7 g of powdered CaCl was incorporated in the gel. The gel was aged 46 days and no change in its properties was noted. To the gel was then added 0.75 ml of water and the whole was shaken for 2 hours. It became slightly less viscous but did not break down. After three days it did break down. However, the gel was very much more resistant to the effects of water than an identical gel without added CaCl- EXAMPLE 4 Two separate samples of gelled heptane were prepared using C l-l OLi and B(OC H as the gelling reagents at a 1 weight per cent level.

To one gel sample was added 4.7 g of MgSO and to the other was added 4.7 g of A1 0 Both samples were thoroughly mixed and each contained 10% by weight of the dehydrating agent. Both gel samples slowly ungelled upon standing and after 7 days the samples were no longer viscous.

This example demonstrates that not all dehydrating agents are compatible with the gelling reagents for a long period of time.

EXAMPLE 5 0.25 g l mmole) of C l-[ 0M was dissolved in 24 g of heptane heated to 60 C. and to the solution was added 4.7g of iron powder followed by 0.23g of B(OC l-l in 24 g of heptane. A gel formed instantly which was shaken well to get a good dispersion of the iron powder. The gel was attracted by a magnet and when the magnet was moved up the side of the glass jar containing the gel, the gel was pulled up far above its original level. The iron particles could be seen to align in the magnetic flux like iron filings on a sheet of paper over a magnet except that in the gel the particle pattern was three dimensional.

EXAMPLE 6 A gel was prepared as described in Example 5 except that benzene was the hydrocarbon and 15.67 g of iron powder was incorporated uniformly throughout the gel. The 4 02. glass jar containing the gel could be lifted and held in midair by a small horseshoe magnet.

While the above Examples of improved gels having increased resistance to hydrolytic degelation employ particular weight per cents of dehydrating agents, this invention is not limited to those amounts. The amount of the dehydrating agent employed may be from 0.1 wt. per cent to wt. per cent depending upon how great an increased resistance to hydrolytic degelation is de sired.

In the case of the magnetic gels, the amount of magnetic material, such as iron filings, contained in the gel may range from 0.1 to weight per cent.

Other dehydrating agents that may be used include NaOl-l, KOH, P 0 boric anhydride, ZnCl,, CaSO, and BaO. Those which cannot be used are protonic acids such as H 80 and I-I PO as well as reactive metals such as sodium and very strong oxidizing agents such A gas or oil well fracturing fluid using the improved gels of this invention may be composed of from 1 to ca. 90 percent by weight of sand or other coarse solid material.

EXAMPLE 7 To a solution of 1.83 g (15.5 mmoles) of Z-butoxyethanol (CH3(CH2)3OCH2CH2OH) in 20 ml of pentane was added 15.5 mmoles of butyl lithium solution dropwise with stirring. The reaction mixture was stirred for one hour after addition of butyl lithium was complete and then the solvents were stripped off under reduced pressure leaving 1.87 g of clear, slightly viscous alkoxide.

A 0.18 g (1.47 mmole) portion of the above lithium alkoxide was dissolved in enough heptane to make 26 g of clear colorless solution. A solution of 0.34 (1.47 mmole) of B(OC,H in 26 g of heptane was prepared and the two solutions were combined with stirring. A very viscous clear liquid resulted. After standing for minutes the material was a soft gel containing 1 weight per cent of gelling reagents.

EXAMPLE 8 The lithium alkoxide of 2-(2-butoxyethoxy)-ethanol [l.e., g, was prepared from 2.51 g of 2-(2-butoxyethoxy)ethanol by the procedure described in Example 7.

A 0.22 g (1.31 mmole) portion of the alkoxide was dissolved in 26 g of heptane and to the solution was added 0.30 g (1.31 mmole) of B(OC H also dissolved in 26 g of heptane. Instant thickening occurred when the two solutions were combined and after 10 minutes a soft gel resulted.

EXAMPLE 9 The lithium alkoxide of (CH ),NCH,CH OH, 1.45 g, was prepared from 1.38 g of the amino alcohol by the procedure described in Example 7.

A 0. l 5 g portion of the alkoxide ((CH NCl-1 CH OLi) was dissolved in enough heptane of make, 26 g of solution. To the alkoxide solution was added a solution of 0.37 g of tri-n-butyl borate (B(OC H in 25.6 g of heptane with stirring. After two minutes, the heptane was a very viscous fluid.

What is claimed is:

l. A composition of matter comprising a gelatinous hydrocarbon containing a minor amount of a compound having either the formula MOR or in combination with a compound having the formula M'(0R')3 in a molar ratio ranging from 3:1 to 1:3 equivalents of either MOR or to M'(OR' wherein M is one selected from the group consisting of Group IA metals; M is one selected from the group consisting of Group IlIA metals; R and R are independently selected from the group consisting of C -C straight or branched hydrocarbyl radicals; R" and R' are the same or different wherein each is a C -C straight or branched hydrocarbyl radical; Q is O or N; A is a hydrocarbyl group containing from 2 to 4 methylenic carbon atoms having 0 to 2 substituents, said substituents being one selected from the group consisting of C -C alkyl, C -C cycloalkyl, phenyl,-

C -C alkenyl, C -C alkynyl, Cl, Br, I; n is an integer ranging from 1 to 10 inclusive; x is an integer and is either l or 2 depending on the valence of O; y is either 0 or 1 depending on the valence of Q; in combination with an amount ranging from 0.1 percent by weight to percent by weight of said composition of a dehydrating agent, said agent being one selected from the group consisting of powdered calcium chloride, magnesium sulfate, calcium carbide, sodium sulfate, calcium oxide, NaOl-l, KOl-l, P 0 boric anhydrides, zinc chloride, calcium sulfate and barium oxide.

2. The composition of claim 1 wherein M is selected .from the group consisting of boron and aluminum.

3. The composition of claim 1 wherein R and R are alkyls independently selected from the group consisting Of C4 to C18.

4. The composition of claim 1 wherein said hydrocarbon boils between 30 and 350 C.

5. The composition of claim 1 wherein M is selected from the group consisting of Li and Na.

6. The composition of claim 1 wherein R is selected from the group consisting of C., to C alkyl radicals.

7. The composition of claim 1 wherein R is selected from the group consisting of C to C alkyl radicals and M is selected from the group consisting of B and Al.

8. The composition of claim I wherein said hydrocarbon boils substantially between 30 and 350 C., MOR is n-C l-l OLi and M'(OR) is B(OC H 9. A composition according to claim 1 wherein the hydrocarbon is liquefied petroleum gas (LPG) and the dehydrating agent is calcium chloride.

10. A composition according to claim 1 wherein the hydrocarbon is diesel fuel and the dehydrating agent is calcium chloride.

11. A composition according to claim 1 wherein the compounds having the general formula MOR and M'( OR are present in the amount ranging from 0.25 to 5 percent by weight of the hydrocarbon.

12. A composition according to claim 1 wherein one of said minor compounds is: CH CH,CH CH OCH,C- H OLi.

13. A composition according to claim 1 wherein one of said minor compounds is: CHaCHgCHgCHgOCHgC- H OCH CH OLi.

14. A composition according to claim 1 wherein one of said minor compounds is: (CH;),NCH,CH,OL1.

15. A composition according to claim 1 wherein the mole ratio of either MOR or R: (ZABOM "a.

to M'(OR) is 1:1.

i 'B t i t 

2. The composition of claim 1 wherein M'' is selected from the group consisting of boron and aluminum.
 3. The composition of claim 1 wherein R and R'' are alkyls independently selected from the group consisting of C4 to C16.
 4. The composition of claim 1 wherein said hydrocarbon boils between 30* and 350* C.
 5. The composition of claim 1 wherein M is selected from the group consisting of Li and Na.
 6. The composition of claim 1 wherein R is selected from the group consisting of C8 to C12 alkyl radicals.
 7. The composition of claim 1 wherein R'' is selected from the group consisting of C4 to C8 alkyl radicals and M'' is selected from the group consisting of B and Al.
 8. The composition of claim 1 wherein said hydrocarbon boils substantially between 30* and 350* C., MOR is n-C16H33OLi and M''(OR'')3 is B(OC4H9)3.
 9. A composition according to claim 1 wherein the hydrocarbon is liquefied petroleum gas (LPG) and the dehydrating agent is calcium chloride.
 10. A composition according to claim 1 wherein the hydrocarbon is diesel fuel and the dehydrating agent is calcium chloride.
 11. A composition according to claim 1 wherein the compounds having the general formula MOR and M''(OR'')3 are present in the amount ranging from 0.25 to 5 percent by weight of the hydrocarbon.
 12. A composition according to claim 1 wherein one of said minor compounds is: CH3CH2CH2CH2OCH2CH2OLi.
 13. A composition according to claim 1 wherein one of said minor compounds is: CH3CH2CH2CH2OCH2CH2OCH2CH2OLi.
 14. A composition according to claim 1 wherein one of said minor compounds is: (CH3)2NCH2CH2OLi.
 15. A composition according to claim 1 wherein the mole ratio of either MOR or 